PROJECT SUMMARY A growing body of research documents that early-life environments play an important role in shaping child and adult well-being. We now know that in-utero and early-life exposure to compromised health environments (e.g., disease exposure, malnutrition) often produces adverse effects that persist well into adulthood. Many government programs aim to counteract these negative effects by providing better access to nutrition, health care, and early education. Recent studies find that childhood access to some of these programs (e.g., Food Stamps, WIC, Head Start, Medicaid) lead to later-life improvements in individuals' health and economic outcomes. Taken together, these two literatures?documenting the impacts of negative health ?shocks? and the impacts of positive investments?make clear that early-life influences have long-lasting effects. Yet, we know surprisingly little about why the effects persist, nor do we know the scope for later-life investments to mitigate the long-run effects of early-life trauma. We also do not know the extent to which later positive investments sustain (or even amplify) the beneficial impacts of early social investments. Moreover, existing studies typically focus on examining the impacts of specific health events or investments in isolation and ignore how additional events or later investments might alter the trajectory of early-life experiences. A key aim of this project will be to test how these programs interact with each other across the life course and into the next generation. We will also investigate whether later-life interventions can reduce the persistent effects of early-life health shocks. To achieve these goals, we will leverage policy variation across space and over time, including county-level variation in the initial ?rollout? of the Food Stamp and WIC programs, and state level differences in the 1980s Medicaid expansions. We will link these program data to different sources of administrative and survey data, which will provide us with very large samples that maximize statistical power, increase our ability to uncover mediators, and detect the presence of interactive effects. The dataset describing how the policies rolled out and associated caseloads and spending will be made available to all interested researchers. Together, these projects will allow us to examine a wide range of intermediate- and long-term outcomes and will provide new information on the efficacy of government policies intended to mitigate health and economic inequalities. For example, understanding the extent to which public health investments mitigate the effects of health ?insults? is an important step towards identifying which government interventions can most effectively reduce long-run health inequalities. Our work will also be critical for understanding the role of the safety net in combating many early life challenges faced by disadvantaged children. Finally, our work will directly inform economic models of human capital and technology of skill-formation. 1